Oral delivery of medications is one of the most frequent techniques utilized for delivering medication to the body. One of the most popular delivery mechanisms is the capsule. The background of U.S. Pat. No. 8,361,497 issued to Miller provides a detailed description into the history and present techniques for capsule manufacture and is hereby incorporated by reference.
Capsules containing medication for oral intake is usually swallowed since it is designed for delivery of the medication to the stomach, where the capsule dissolves within 20 to 30 minutes and the medication is absorbed into the bloodstream.
In certain medical emergencies like acute coronary insufficiency, angina, hypertensive crisis, life threatening arrhythmias, epileptic aura seizures, it is required to deliver the medication to the bloodstream in one to two minutes. That could be accomplished by direct intravenous infusion of medication which is the preferred route used in medical emergencies in a hospital setting.
While intravenous injection is the fastest way to deliver a medication to the bloodstream, self-administration via intravenous injection is not a common practice.
The only other for delivery of medication within minutes to the bloodstream is sublingual administration or rectal instillation. Nitroglycerin is the only example that is used intravenously, sublingually as a liquid or tablet or rectally as an ointment. In all situations, the medication reaches the bloodstream almost immediately manifesting the effect by headache.
Liquid nitroglycerin given via pumpspray sublingually is competitive even when the intracoronary route of nitroglycerin administration is used in a catheterization laboratory. One problem with use of a pumpspray is that it is manufactured to delivery 60-200 doses. Such spray container has no limit on the number of doses a patient can administer in rapid succession. Thus, the possibility exists for the patient to overdose by spraying multiple doses with potential to incur life threatening side effects such as syncope, drop-attacks, etc.